<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        span:before {
            content: '123';
            display: inline;
            background-color: #3c763d;
        }
        span:after{
            content: '456';
            display: inline;
            background-color: #3c763d;
        }
    </style>
</head>
<body>
<span>456</span>
</body>
</html>